The polymerization of olefins such as ethylene, propylene, norbornene and cyclopentene are very important commercial processes. These are most commonly done using polymerization catalyst systems containing certain transition complexes. For instance, the Zielger-Natta-type catalysts and metallocene-type catalysts are some of the more important and well-known catalysts of this type which are used to make billions of kilograms of polyolefins annually. Due to the importance of the polymerization of olefins, new catalyst systems are constantly being sought.
Japanese Patent Application 10/36,424 shows a formula for a bis(carboximidamidatonate), but neither describes how to make such a compound nor actually does a polymerization with such a compound.
A. Littke, et al., Organometallics, vol. 17, p. 446-451 (1998); V. Volkis, et al., ibid, p. 3155-3157; J. C. Flores, et al., Organometallics, vol. 14, p. 2106-2108 (1995); P. J. Stewart, et al., ibid, p. 3271-3281; H. W. Roesky, et al., Chem. Ber., vol. 121, p. 1403-1406 (1988); and D. Herskovics-Korine, et al., J. Organometal. Chem., vol. 503, p. 307-314 (1995); report the synthesis and/or use of transition metal complexes of two independent (mono)carboximidamidatonate ligands as polymerization catalysts. However, in none of these references are the two carboximidamidatonates groups joined by a common moiety such as a benzene ring.
A. Littke, et al., Organometallics, vol. 17, p. 446-451 (1998) and S. L. Aelits, et al., ibid, p. 3265-3270, describes the formation of carboximidamidatonates by the reaction of an organometallic compound with a carbodiimide. The use of a bis(alkyl metal salt) to form a bis(carboximidamidatonate) is not described.